Apparatus for cutting vegetation

Abstract

An apparatus for cutting vegetation with a rotating head carrying a flexible, non-metallic cutting line extended radially into a cutting plane. An additional length of line is extended into the cutting plane by pushing the head against the ground and rotating the head. A glide ball on the head moves inwardly for releasing a spool carrying coiled cutting line to rotate a predetermined angular displacement in the head. After the cutting line length is extended, the spool is secured automatically against further rotation within the head. In a preferred embodiment of the apparatus, the glide ball is pressed against the earth's surface with the head in a non-rotating condition. Then, the head is rotated for extending the cutting line from the head to the certain desired length. Then, the spool is secured automatically against rotation relative to the head.

What is claimed is: 
     
       1. An apparatus for cutting vegetation, comprising: (a) a head rotatable about an axis of rotation with a drive connection extending from a first face and a second face having a smooth convex surface free of projections and recesses capable of trapping appreciable vegetation and said head having an open-ended cylindrical cavity coaxial with the rotational axis;   (b) a spool carried by said head and mounted for rotation independently thereof within said cavity, and said spool comprised of two spaced-apart circular flanges aligned in parallel and mounted upon a tubular reel body having a cylindrical interior wall surface with open ends;   (c) a cylindrical post member mounted coaxially within said cavity on said head, and provided with bearing means to journal said spool for rotation about said post member and adapted for axial movement thereon between an outward station and an inward station;   (d) resilient means biasing said spool into the outward station;   (e) a flexible, non-metallic cutting line coiled on said spool and having a free end extending outwardly of said head through aperture means into a cutting plane;   (f) a circular glide ball member conforming to the smooth convex surface and mounted on said spool concentrically with the rotational axis for enclosing one open end of said spool; and   (g) locking means on said spool and post member, said locking means adapted to be activated by said glide ball member moving said spool between the outward and the inward stations for releasing said spool for rotation within said head responsive to pull of the free end of said cutting line, said locking means including a plurality of inwardly-facing radially-aligned teeth carried by said spool upon the cylindrical interior wall surface and a plurality of outwardly-facing radially-aligned pins carried on said post member, and said teeth and pins cooperating in angular and axial spaced relationships for regulating spool rotation through a predetermined angular displacement for extending a certain length of cutting line from said head into the cutting plane when said spool moves between said inward and outward stations whereat said locking means with said spool at the outward station on said post member securing said spool against rotation relative to said head.   
     
     
       2. The apparatus of claim 1 wherein said glide ball member extends substantially coextensively of the convex smooth surface of said spool and is integral therewith. 
     
     
       3. The apparatus of claim 1 wherein said glide ball member has a rounded surface adapted to engage vegetation-covered earth's surface for manual displacement from the outward station to the inward station. 
     
     
       4. The apparatus of claim 3 wherein said glide ball member has a low-friction smooth surface relative to vegetation whereby said head can be rotated in contact with vegetation without excessive torque requirements. 
     
     
       5. An apparatus for cutting vegetation, comprising: (a) a head rotatable about an axis of rotation with a drive connection extending from a first face and a second face having a smooth convex surface free of projections and recesses capable of trapping appreciable vegetation and said head having an open-ended cylindrical cavity coaxial with the rotational axis;   (b) a spool carried by said head and mounted for rotation independently thereof within said cavity, and said spool comprised of two spaced-apart circular flanges aligned in parallel and mounted upon a tubular reel body having a cylindrical interior wall surface with open ends;   (c) a cylindrical post member mounted coaxially within said cavity on said head, and provided with bearing means to journal said spool for rotation about said post member and adapted for axial movement thereon between an outward station and an inward station;   (d) resilient means biasing said spool into the outward station;   (e) a flexible, non-metallic cutting line coiled on said spool and having a free end extending outwardly of said head through aperture means into a cutting plane;   (f) a circular glide ball member conforming to the smooth convex surface and integrally mounted on said spool concentrically with the rotational axis for enclosing one open end of said spool; and   (g) a plurality of inwardly-facing teeth carried at uniform angular spacings upon the cylindrical interior wall surface of said spool;   (h) a plurality of outwardly-facing pins carried by said post member, said pins residing at different horizons relative to the axis of rotation and in radially opposite positions on said post member; and   (i) said teeth on said spool engaging some of said pins at one horizon on said post member when said spool is at the outward station and said teeth on said spool engaging other of said pins at another horizon on said post member when said spool is at the inward station, whereby said teeth and pins cooperate at the inward station for regulating spool rotation through a predetermined angular displacement for extending a certain length of cutting line from said head into the cutting plane, whereat said spool at the outward station is locked on said post member for securing said spool against rotation relative to said head.